Process of and apparatus for burning fuel



(No Model.) 5 3 Sheets- Sheet 1.

' P. H. RICHARDS.

PROCESS OF AND APPARATUS FOR BURNING FUEL. N0. 535,4 Patented Mar; 12,1895.

I Wz'tn eases: figwm g I ZZed KM (No Model.) 3 Sheets-Sheet 2.

F. H. RICHARDS.

PROCESS OF AND APPARATUS FOR BURNING FUEL. No 5355413. Patented Mar. 12,1895.

Witnesses: Inventor.-

OM NM (No Model.) 3 Sheets-Sheet 3.

P. H. RICHARDS. PROCESS OF AND APPARATUS FOR BURNING FUEL.

No. 535,413. PatentedMar. 12, 1895-. I

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? 'Ni'rnn STATES ATENT Orrrcn.

FRANCIS I-I. RICHARDS, OF HARTFORD, CONNECTICUT, ASSIGNOR TO EOKLE B.COXE, OF DRIFTON, PENNSYLVANIA.

PROCESS OF AND APPARATUS FOR BURNING FUEL.

SPECIFICATION forming part of Letters Patent No. 535,413, dated March12, 1895.

Application filed October 30, 1894- Serial No. 527,424:- (No model.)

To all whom it may concern.-

Be it known that I, FRANCIS H. RICHARDS, a citizen of the United States,residing at Harte ford, in the county of Hartford and State ofConnecticut, have invented certain new and useful Improvements inProcesses of and Apparatus for Burning Fuel, of which the following is aspecification.

This invention relates to processes of and apparatus for burning fuel,and resides more particularly in the process which is in the nature ofan improvement on the process described and claimed in Letters Patent ofthe United States No. 499,715, granted to Eckley B. Coxe June 20, 1893,to which reference may be had.

The object of my present invention is to furnish an improved process andapparatus adapted, not only for burning the smaller sizes of anthracitecoal, including those sizes known in the marketas pea, buckwheat, dad,but also adapted for burning the smaller sizes,.or crushed, bituminousor semi-bituminous coal with economy and efficiency, and

with the best practical resultsfor heating purposes.

In the drawings accompanying and forming part of this specification,Figure l is a sectional side elevation of a portion of one form ofboiler-heating furnace embodying my invention and adapted for carryingout my improved process. Fig. 2 is a plan view of the same with aportion of the upper part of the furnace broken away. Fig. 3 is atransverse vertical section of the furnace, taken in line a-a, Fig. 1,looking toward the left hand in said figure. Fig. 4 is a side elevationof one of the reciprocatory members of the fuel-agitating grate. Fig. 5is a rear elevation of said 4.0 member. Fig. dis a front elevation ofsaid member, and Figs. v7 and 8 are side and rear elevations,respectively, of another reciprocatory member of the fuel-agitatinggrate.

Similar characters designate like parts in all of the figures.

In the drawings only so much of a boilerheating furnace is shown as isnecessary for illustrating the construction and mode of op eration of myimprovements, and, as is necessary for illustrating the successive stepsin my improved process of burning fuel.

According to the process described and claimed in the Patent No. 449,715hereinbefore referred to, it will be remembered that a fuel-travelingfurnace-floor was employed for 5 carrying the fuel throughout thefurnace chamber and that the coal or other fuel to be burned is,according to that process, first placed in a mass or layer of properthickness upon the furnace-floor, is then ignited and 6' subsequentlysubjected to an air-blast the pressure of which is varied or graduallyreduced (either continuously or intermittently) during the combustionperiod, so that the ignited mass is subjected to varying or success- (isively-reduced pressure-blasts during the successive stages of the saidcombustion period; and furthermore it will be remembered that said-layerof fuel is maintained substantially inst/a ter qtto during the entireseries of the successive stages of the combustion period, no portion orportions thereof being subjected to agitation during combustion.

In practice, it has been found highly advantageous for the facilitationof combustion, especially when bituminous coal is used to subject thefuel, during its traveling movement, to slight agitation .during theearlier stages of the combustion period, or those stages of thecombustion period immediately preceding the preparatory stage or theignition period, and to subject said agitated mass of fuel to aerationby a relatively high-pressure airblast; in that a slight agitation ofthe fuelat this stage in the combustion period loosens and inter-mixesthe fuel to such an extent as to prevent fusion, and practicallyobviates autogenous soldering of the congruous elements of the materialinto a homogeneous mass, and by aerating this agitated mass through themediu mof a relatively high-pressu re blast, said mass is practicallyfreed from minute particles, such as dust, which minute particles willbe consumed by the superheated atmosphere of the furnace-chamber, afterwhich, said ma- 5 terial may be delivered into position for furthertreatment in the process of combustion, in a refined or purified andseparated condition.

Therefore, my present invention in part, particularly resides in animproved process of burning fuel, which consists in first feeding thefuel in a continuous and continuouslyadvancing, and relatively thin,layer or stream, and simultaneously heating said layer without aeration,next igniting and moving said relatively thin layer onward andsimultaneously subjecting the same to agitation and aeration to therebybring the layer, at this point in the combustion period, to a high stateof incandescence, without materially increasing the thickness of saidlayer, and next re-forming the advancing incandescent layer into arelatively thick layer, and moving said relatively thick layer onward,and subjecting the same to aeration without agitation, and maintainingthe same substantially in stattt quo during the latter successive stagesof the combustion period, as will be hereinafter more fully described.

In the preferred form thereof herein shown and described, the furnacefor carrying out my improved process may, in a general way, be similarto the furnace shown and described in the patent hereinbefore referredto, it having a furnace-chamber, O, inclosed at its sides and ends bythe side-walls, 2 and 4, and endwalls, 3 and 5, and is covered by areverberatory-roof, A, the construction and function of which will behereinafter described. The furnace is also shown provided with aflue-boiler, B, at the rearward end thereof and is also shown having acombustion-chamber, O, at the rearward end of the furnace-chamber, G,and immediately adjacent to the forward fluesheet of the boiler, B.

As a means for carrying the fuel, designated by F, longitudinally of thefurnacechamber and maintaining the same substantially in statu quoduring the latter stages of the combustion period and to agitate andintermix the same at a point coinciding with the first stages of thecombustion period, I have provided a furnace-floor which, in thepreferred form thereof herein shown and described, consists of twoseparate and independently-operable grates, designated in a general wayby G and G, respectively, the one G, which will be herein termed thefuel-agitating grate, being shown in the nature of a reciprocatorystoking grate and being supported with its receiving end contiguous tothe front end of the furnace-chamber and in oblique alignment with thedelivering end of the chute, 7, of a fuel-supply hopper, H, located atthe front end of the furnace; where as the grate, G, is in the nature ofa progressively-movable endless chain grate and may be similar inconstruction and organization to the endless chain grate shown in thePatent No. 499,715 hereinbefore referred to, said chain grate, G, beingsupported for traveling movement longitudinally of the furnace-chamberwith its receiving end below the delivering end of and in position toreceive the fuel as it is delivered from the fuel-agitating grate G; thedelivering end of said endless grate extending under and in closeproximity to a bridgewall, 5, in a manner similar to that shown in thepatents hereinbefore referred to. This grate is carried at the oppositeends of its circuit by chain-wheels, 12 and 14, which are carried uponshafts, 13 and 15, journaled in suitable bearings, 13 and 15', upon theside-walls of the furnace-structure. As a means for actuating saidendless grate toimpart a continuous movement to the fuel supportedthereon, the shaft 13 is provided at one end thereof with a worm-wheel,40, which meshes with a worm, ll, on a driving-shaft, 42,which shaft issupported in suitable bearings, 43 and 43', upon the frame-work, and isshown provided at one end thereof with a cone-pulley, 4a, which ispreferably driven in a manner hereinafter more fully described.

In the form thereof herein shown and described, the reciprocatory stokeror fuel-agitating grate, G, comprises a series of inclined members orsections, g, each having a series of horizontallyand remotely-disposedfuelsupporting steps, 8, and supported at their upper and lower ends forhorizontal reciprocation in guide-ways, 9, and 9, preferably formed bytransverse plates secured to the side-walls of the furnace-structure.These members, g, are so disposed relatively to each other thatthefuel-supporting shelves or steps, 8, of one member will overlap theshelves or steps of the next adjacent member in such manner as to leaveair-spaces, 8', between the overlapping fuel-supporting steps.

As a means for actuating the reciprocatory or fuel-agitating grate sothat certain of the members thereof shall have an advancing movementduring the retracting movement of others of said members, I haveprovided a grate-actuating mechanism which in the preferred form thereofherein shown, consists of aseries of eccentrics, 16, carried upon atransverse shaft, 17, journaled in suitable bearings in the side-wallsof the furnace-structure, and connected, each of said eccentrics, with agrate-member, g, by means of an eccentricstrap, 18, and connecting-rodor link, 19, as will be readily understood by reference to Figs. 1 and 2of the drawings.

As a means for actuating the shaft, 17, to impart a reciprocatorymovement to the several grate-members, g, said shaft is shown providedat one end thereof with a bevelgear, 20, which meshes with a bevel-gear,21, of relatively small size, upon a shaft, 22, journaled in bearings,23 and 23', upon the sidewalls of the furnace-structure, which shaft,22, is provided atone end thereof with a conepulley, 24:, which may bedriven from any suitable source of power (not shown).

As a means for operating the fuel-agitating grate, G, and thenon-agitating grate, G, at comparative velocities of va rying ratios,the driving-shafts of these two grates are preferably operativelyconnected together, as most clearly shown in Figs. 1, and 3, by a belt,25, extending over the two pulleys, 24 and 44, upon the shafts, 22 and42, respectively, the relative difference in the velocities of the twogrates, G and G, being governed by variable speed-gearing, as shown in,and as will be understood by reference to, Figs. 1, 2 and 3 of thedrawings.

In practice, that portion, G, of the furnacefioor (herein termed thefuel-agitating grate) immediately adjacent to the ignition end of thefurnace-chamber will have a relatively rapid fuel-traveling movement,and that portion, G, of the furnace-floor (designated the endless grate)immediately adjacent to the portion G of the furnace-floor, will have arelatively slow fuel-traveling movement, so that, in operation, thelayer of fuel, F, as it passes from the front portion, G, to the rearportion, G, of-the furnace-floor will be reformed into a relativelythick layer, as will be hereinafter more fully described.

As a convenient means for regulating the supply of fuel to thefurnace-floor, to secure the requisite thickness of layer at theignition end of the furnace-chamber, the fuel-supply hopper, H, willusually be provided with a suitable gate, 26, for increasing ordecreasing the effective area of the outlet opening of said hopper.

Between the hopper, H, and the receiving end of the furnace-floor, Iplace a block, B, designated as the ignition-block, over which the fuelpasses in its descent from the hopper, H, to thefurnace-floor. Thisignition-block, B, has its inclined surface or slope 7 set facing thefurnace-chamber and is preferably constructed of refractory material oflow conductivity, such as fire-brick or other furnacebuilding materialof similar character. Said block or hot-slope is supported upon asuitable plate or beam, 27, of thefurnace-structure. The ignition-blockis set in close proximity to the receiving end of the furnacefloor withits inclined face in substantial align,- ment with the normal angle ofrepose of the fresh fuel, so that the stream or layer falling down oversaid block will be subjected,

in a continuous and continuously movingv layer, to heating,simultaneously, from above and below without aeration, thus preparingthe fuel for sudden subsequentignition. The ignition-block is designatedas non-aerating for the reason that it is so made as to protect thefuel, during the preparatory heating from the admission of air frombelow, which admission of air would tend to prematurely liberate andignite the gases of the fuel, and would also cool said block and therebyprevent the proper underheating of said fuel.

In accordance with my present process, the fuel, F, is delivered to theforward end of the furnace-floor in a relatively thin stream withoutaeration or agitation; is then ignited and advanced and, during theearliest stages of the combustion period, is simultaneously subjected toagitation and aeration,without materially increasing the thickness ofsaid layer, after which this thin incandescent or partially consumedlayer is re-formed into a relatively thick layer and further advancedwithout agitation, throughout the entire length of the furnace-chamber,and is maintained substantially in statuquo during the latter stages ofthe combustion period.

The arched-roof, A, of the furnace-chamber is set to reflect a portionof the heatedrays of the furnace backward and downward upon theignition-block, B. This arrangement has the effect .of increasing theefiiciency of the apparatus for the heating of the incandescent streamof fuel upon the said ignition-block. In passing downward over saidblock the inclined column, 32, of granular fuel that naturally partakesof the usual movements of the stream has within itself variable rates ofmovement; so that during the descent of the fuel over the inclinedsurface of the block, 13,

the particles of the fuel are shifted or turned over more or less andare thereby more fully exposed to the action of the heated gases withinthe furnace-chamber.

For a full illustration of the principle of the invention, referenceshould now be had to Fig. 1 of the drawings, where the layer of fuel isshown divided longitudinally into three spaces or divisions, designatedby D, D and D respectively, which correspond in position to threesuccessive stages in the combustion period of the fuel. The division D,represents the preparatory heating area of the fuel, at which point thefuel is subjected to heating from above and below without aeration, andconditioned for subsequent sudden ignition. The division D representsthe ignition and relatively high combustion area, at which area theadvancing layer of fuel is ignited, agitated and intermixed, and aeratedby a relatively high-pressure air-blast from below, to bring thisportion of the layer of the fuel to a high state of incandescence,separate the minute particles, such as coal-dust, from said layer andforce them outward into the combustion-chamber, and at the same timepractically obviate autogenous soldering of the congruous elements ofthe material into a homogeneous mass, and condition them for a furthertreatment in a purified and separated condition, and the division Drepresents the last or completing stages of the combustion area, or thatportion of the fuel-area immediately in advance of the agitated portionof the layer and where the fuel is re-formed into a relatively thicklayer and maintained substantially m statu quo during its travelingmovement, throughout this area or throughout the latter stages of thecombustion period.

In practice, it is desirable to subject the successive f uel-areas, Dand D to forced airblasts of varying pressures to facilitate and promotecombustion, the best results being obtained by subjecting the fuel-area,D, to a relatively high-pressure air-blast and to subject the fuel-arearepresented byD to an airblast, which is of gradually reduced pressure,

from the forward to the rearward end of said area so as to burn the fuelsomewhat after the method described in Patent No. 499,715, hereinbeforereferred to. The action of the airblasts upon the layer of fuel, in thepresent instance, being substantially the same as in the patent referredto, but, owing to the changes in condition of the fuel during itstraveling movement and at different points in the length of thecombustion period, the effect of the air-blast differs materially fromthe effect described in said patent, as do also the results attainedthereby.

As a means for supplying air to the fuel, I have provided an air-blastapparatus which, in the preferred form thereof shown in full lines inFig. 1 of the drawings, is in the nature of an air-supply chamber, a,which is located below the furnace-floor and extends approximately fromend to endthereof, it being closed adjacent to the delivering end of thefurnace-floor and being cut off from the area above the furnacefloor bymeans of transverse partitions, 33 and 38, one partition 33, of which islocated between the upper and lower runs, 10 and 11, respectively, ofthe endless grate, G, and the one, 33, of which is located below thelower run, 11, of said grate. This air-supply chamber, a, may besupplied with air through the inlet opening, 34, by means of a blower(not shown) or in any suitable manner. This constitutes a very simpleand effective air-supply apparatus for the fuel, and, owing to therelatively varying thicknesses and owing to the variation in the densityof the fuel at successive points in the length of the layer, it will beseen that the volume of air supplied from the chamber, a, through thefuel will be of varying efficiencies at successive points in the lengthof the fuellayer and, by regulating the supply of fuel to thefurnace-floor, to increase or decrease the thickness of the layer at thesuccessive areas, D, D and D Thevarying proportions of air-supplies atthese successive areas may be nicely adjusted to increase or decreasethe effective supply of air to these successive areas and consequentlysecure the best possible results in the combustion of the fuel andobviating the necessity of employing separate valve-regulated air supplychambers below and at successive points in the length of thefurnace-floor, as described in the patent hereinbefore referred to.

It will be understood, however, that I do not desire to limit myself tothe air-supply apparatus just described as, with certain kinds of fuel,it may be desirable to employ, in connection with the furnace-floor, aseries of successive air-supply chambers having outlets contiguous tosuccessive fuel-areas as illustrated in lines, 1), in Fig. l of thedrawings, which chambers will be adapted for supplying air to the fuelat varying pressures at successive points in the length thereof, asdescribed, for instance, in the patent hereinbefore referred to.

In operation, the fuel-agitating grate, G, which receives the fuel as itdescends from the ignition-block B, will be actuated to impart arelatively rapid advancing movement to the layer, and, at the same time,agitate and intermix the constituents of said layer, delivering the sameto the endless grate, G, which grate, for the purposes of the presentinvention, has a relatively rapid velocity as compared with the velocityof the grate, G, to thereby carry the fuel to the latter stages of thecombustion period, with a relatively slow movement; this difference inthe velocities of the two grates G and G, respectively, causing the fuelto be re-formed, at the adjacent ends of the two grates, into arelatively thick layer which is not subjected to agitation after itleaves the grate, G, but is maintained substantially in statu quothrough the remaining stages of the combustion period; said layer, ofcourse, being gradually reduced in thickness by consumption as itapproaches the last stage of the combustion period, after which theresultant cinder and ash will be carried over the delivering end of theendless grate and discharged into the usual ashpit, P.

By my improved process and apparatus, I not only secure an accelerationin the combustion of the fuel, but I also secure a more completeconsumption of the fuel than is possible with methods and apparatus inwhich no provision is made for subjecting the fuel to agitation for thepurpose of freeing the same from dust, and for obviating autogenoussoldering of the congruous elements thereof, and especially is this soin the combustion of bituminous and semi-bituminous coal.

Having thus described my invention, I claim 1. The herein-describedprocess of burning coal and other fuel, which consists in igniting themass spread in a layer, subjecting the same to agitation and aerationduring the first stages of the combustion-period, maintaining the samesubstantially in statu quo during the latter stages of thecombustionperiod, and subjecting the same to the action of a forcedair-blast during said latter stages, substantially as described.

2. The herein-described process of burning coal and other fuel, whichconsists in igniting the mass spread in a layer, subjecting the same toagitation during the first stages of the combustion-period, maintainingthe same substantially in statu, quo during the latter stages of thecombustion-period, and subjecting the same to the action of a forcedairblast throughout the whole of the combustion-period, substantially asdescribed.

3. The herein-described process of burning coal and other fuel, whichconsists in igniting the mass spread in a layer, imparting acontinuously-advancing movement to said layer, subjecting said layer toagitation during the first stages of the combustion-period, maintainingsaid layer substantially in Sta-m quo during the latter stages of thecombustion- IIO period, and subjecting said layer to the action of aforced air-blast throughout the whole of the combustion period,substantially as described.

4. The herein-described process of burning coal and other fuel, whichconsists in igniting the mass spread in a layer, subjecting the same toagitation during the first stages of the combustion period, maintainingthe same substantially in statu quo during the latter stages of thecombustion period, and subjecting said layer to an air-blast havingvarying efficiencies at successive points in the length of the layer,substantially as described.

5. The herein-described process of burning coal and other fuel, whichconsists in igniting the mass spread in a layer, imparting acontinuously advancing movement to said layer, subjecting said layer toagitation during the first stages of the combustion period, maintainingsaid layer substantially in statu quo during the latter stages of thecombustion period, and subjecting said layer to an air-blast havingvarying efficiencies at successive points in the length of the layer,substantially as described.

6. The herein-described process of burning coal and other fuel,whichconsists in feeding the fuel in a continuous and continuously advancinglayer, first in a relatively thin layer downwardly in inclination, andheating the same from above and below, simultaneously, without aeration,next continuing the advancing movement of said layer without materiallychanging the thickness thereof, and agitating and mixing said advancinglayer and simultaneously subjecting the same to aeration, and nextre-forming said layer into a relatively thick layer and continuing theadvancing movement thereof, maintaining the same substantially in statuquo during the latter stages of the combustion period, and subjectingsaid layer to aeration without agitation during the latter stages of thecombustion period, substantially as described.

7. The herein-described process of burning coal and other fuel, whichconsists in igniting a mass spread in a layer, imparting acontinuously-advancing movement to said layer of varying velocities atsuccessive points in the length of its traveling movement toautomatically secure varying thicknesses of said layer at differentpoints in the length thereof, and subjecting said layer from below tothe action of a forced air-blast, substantially as described.

8. The herein-described process of burning coal and other fuel, whichconsists in igniting amass spread in a relatively-thin layer, impartinga relatively rapid advancing movement to said ignited layer andsubjecting the same to agitation and aeration, reforming saidrelatively-thin layer into a relativelythick layer and imparting arelatively-slow advancing movement to said relatively-thick layerwithout agitation, and simultaneously and maintaining the samesubstantially in statu qua during the latter stages of thecombustion-period, and subjecting said layer to the action of a forcedair-blast throughout the traveling movement thereof, substantially asdescribed.

10. In an apparatus for burning coal and other fuel, the combinationwith afurnacechamber, of a fuel-traveling furnace-floor comprising alongitudinally-movable fueltraveling grate, and a second andindependently-operable and progressivelyand longitudinally-movablefuel-traveling grate supported in advance of said first-mentioned grate;and means for actuating said grates at relatively varying velocities,substantially as described and for the purpose set forth.

11. In an apparatus for burning coal and other fuel, the combinationwith a furnace chamber; of a fuel traveling furnace floor comprising alongitudinally-movable fueltraveling grate, and a second andindependently-operable and progressivelyand longitudinally-movablefuel-traveling grate sup ported in advance of said first-mentionedgrate; and means in connection with and adapted for simultaneouslyimparting fueltraveling movements of relatively varying velocities tosaid respective grates, substantially as described and for the purposeset forth.

12. In an apparatus of the class specified, the combination with thefurnace-chamber and its inclosing walls, of a fuel-travelingfurnace-fioor comprising two independent fueltraveling grates supported,one above the other, and adapted for movement longitudinally of thefurnace-chamber, means for supplying air to said fuel-travelingfurnace-floor from below, and means in connection. with and adapted forsimultaneously actuating said grates at relatively varying velocities,substantially as described and for the purpose set forth.

13. In an apparatus for burning coal and other fuel, a furnace-chamber,in combination with an endless fuel-traveling grate, supported formovement within and longitudinally of the furnace-chamber, areciprocatory f uelagitating grate supported with its delivering endabove and adjacent to the receiving end of the endless traveling grate,means in position and adapted for supplying fuel to the receiving end ofthe fuel-agitating grate and means in connection with and adapted forimparting a circuitous movement to the end less grate and areciprocatory movement to the fuel-agitating grate, substantially asdescribed and for the purpose set forth.

14. The hereindescribed apparatus for burning coal and other fuel, itcomprising a furnace-chamber, a fuel-traveling furnacefioor locatedwithin said furnace-chamber, and comprising two independentfuel-supporting and fuel-traveling portions supported in differentplanes and adapted for movement longitudinally of each other, at varyingvelocities, means for supplying fuel to one of said fuelsupportingportions, means in connection with and adapted for actuating saidindependent fuel-supporting portions, simultaneously at relativelyvarying velocities, and means in connection with and adapted forsupplying air to said fuel-supporting portions of the furnace-floor,substantially as described and for the purpose set forth.

15. In an apparatus for burning fuel, the combination with afurnace-chamber, of a nonagitating fuel-traveling grate supported fortraveling movement at the rearward end of said furnace-chamber, afuel-supply hopper supported at the forward end of the furnacechamber, afuel-agitating grate supported above and intermediate to thenon-agitating grate and the fuel-supply hopper, means for supplying airto the fuel supported upon said grates, means for automaticallyregulating the effective supply of air to the fuel to secure varyingefficiencies at successive points in the length thereof, and means inconnection with and adapted for actuating the agitating andnon-agitating fuel-traveling grates, at relatively varying velocities,substantially as described and for the purpose set forth.

16. In an apparatus for burning coal and other fuel, the combinationwith the furnacechamber having a reverberatory arch, of fuelsupplyingand fuel-traveling apparatus comprising a fuel-supply hopper supportedwith its delivering end in communication with the f urnace-chamber, afuel-heating block or ignition-block having an inclined surface facingthe interior of the furnace-chamber and contiguous to and forming aninclined chute for the supply hopper, a fuel-agitating grate supportedfor reciprocation with its receiving end contiguous to the deliveringend of the ignition-block and comprising a series of reciprocatorymembers, a fuel-traveling grate supported with its receiving end belowthe fuelagitating grate and adapted for receiving the fuel as it isdelivered from said fuel-agitating grate and adapted for carrying thefuel onward throughout the furnacechamber, means in connection with andadapted for actuating the two grates at relatively varying velocities,and an air-blast apparatus in connection with and adapted for supplyingair to the fuel upon said grates, substantially as described and for thepurpose set forth.

17. In an apparatus for burning fuel, the combination with thefurnace-chamber and with the endless grate and its actuating-mechanism,of a fuel-agitating grate, supported with its delivering end above saidendless grate in position to deliver fuel thereto and comprising aseriesof reciprocatory members, set side by side, and having horizontallyandremotely-disposed fuel-supporting shelves or steps in overlappingdisposition, the shelves of one member relatively to the shelves of theadjacent member, and means in connection with and adapted forreciprocating said members simultaneously or successively, substantiallyas described.

FRANCIS II. RICHARDS.

\Vitnesses:

FRED. J. DOLE, S. W. PoTTs.

